Tshark "-Tfields" option not working

Tshark Version 2.6.3 (Windows 64-bit version)

I am trying to export the "data.txt" field to a text file with TSHARK. When I attempt the following...

tshark -r filename.pcapng -Tfields -e data.txt >> dataprint.txt

I get the following error...

tshark: Some fields aren't valid: data.txt

Is this a limitation of the current version of Tshark where data.txt is not a field that can be extracted with the TFields parameter? In the default profile, I have "Show data as text" checked in the protocol preferences.